1. Field of the Invention
The present invention relates to a rotor of a rotary electric machine.
2. Description of the Background Art
Conventionally, as a rotor of permanent-magnet-embedded type, there is proposed a rotor in which a nonmagnetic member is engaged with a magnetic member, and an end portion of a magnet embedded in a laminated core is held by the nonmagnetic member, so that the flux leakage from the magnet into an end plate will be reduced (see, for example, Patent Documents 1 and 2).    Patent Document 1: Japanese Laid-Open Patent Publication No. 20104630    Patent Document 2: Japanese Patent No. 4667640
In a rotor disclosed in Patent Document 1, a ring-shaped plate (nonmagnetic material) is pressed to a laminated core by an end plate (magnetic material), so that the ring-shaped plate is fixed. As a result, there is a problem that if soft nonmagnetic material such as a resin or aluminum is used for the ring-shaped plate, the ring-shaped plate is deformed by being pressed by the end plate.
In a rotor disclosed in Patent Document 2, members made from nonmagnetic material, and members made from magnetic material are alternately arranged along the circumferential direction, and these members are fixed being swaged with each other.
In the case where the nonmagnetic members and the magnetic members are fixed in close contact with each other over the whole circumference as described above, when the temperature of the rotor increases owing to iron loss or the like during the operation of a motor, excessive interference occurs between the nonmagnetic members and the magnetic members, because the thermal expansion coefficients are greatly different between the nonmagnetic members and the magnetic members.
Therefore, there is a problem that if soft nonmagnetic material such as a resin or aluminum is used for the nonmagnetic members, the nonmagnetic members are deformed.